In Review: 10mm Auto From DoubleTap

As a huge fan of the 10mm Auto cartridge, it was only natural for me to give the little beast some server space here at Adiga Armory. DoubleTap Ammo has been one of few ammo factories who load the 10mm up to it’s full potential. In this post, we will take a look at 3 of their full-power 10mm loadings to see how they hold up.

Here they are in all of their glory…

1. Left) DoubleTap 10mm Auto – 200g Controlled Expansion/Hornady XTP-JHP
   
2. Center) DoubleTap 10mm Auto – 165g Remington Golden Saber-JHP
3. Right) DoubleTap 10mm Auto – 200g FMJ-FP

All 3 rounds gave me reasonably good accuracy. However, they are not designed to provide match-grade accuracy. If you want match ammo, you have to sacrifice some velocity. These loads are a bit on the warm side, and are designed to hit hard as opposed to making overlapping holes on paper at 50 yards.

Here is the test gun (my backcountry defensive weapon of choice), the venerable Glock model 20 (Gen 3). This one is fortified with a 22lb recoil spring, stainless steel guide rod, and night sights. The rest is bone-stock Glock…

The test medium was water-soaked phone books, the elevation was 5400 ft, and the temp was a balmy 1 degree Celsius. The first rounds I tested were the Golden Saber and the XTP. I wanted to see what they would do to a single book at nearly point-blank range. Here are the results from firing about 5 feet away…

Believe it or not, the image above is actually the entry wound of the Golden Saber at extremely close range. And here is the exit shown below…

The exit wound looks like it was made by 2 separate projectiles… that is sort of what happened. It appears that the Golden Saber literally shattered on impact with the wet mass. There was likely a core-jacket separation which caused the two to exit at different points in the rear. The tissue damage spread to about 5″ from top to bottom… straight up nasty.

Now lets take a look at what the 200g Hornady XTP does to a single phone book inside of 5 feet…

As you can see, the entry wound is significantly more conservative than the Golden Saber was. This is likely due to the fact that this bullet is much slower and heavier. It also has a much less aggressive cavity in the tip which slows expansion, hence the term “controlled expansion”. Despite the conservative entry wound, the exit wound was outrageous…

The XTP damage dwarfs even the respectable Golden Saber load. The exit wound from the XTP at close range disrupted a diameter of nearly 8″ of tissue… truly awesome performance. This is what you might expect from a hot loaded .357 Magnum round out of a long-barrel revolver.

Since both loads easily passed through one book, I didn’t bother to test the FMJ-FP here. Those would have cut through like it wasn’t even there. Next, I placed 2 books back to back to see what happens. Here are the results when shooting from a more reasonable range of 7 yards…

The entry wounds above indicate that the Golden Saber seems to have less of a tendency to explode on impact if you give it a little bit of distance from the muzzle. At this range, they only lose around 30 fps, but I guess it must make a difference.

Here they are coming out of the back of the first book.

Notice the severe necrosis and shock ripples around the wound channels… this means we are beginning to see signs of hydrostatic shock. Both JHP rounds are showing significant deformation by this point. Remember, one phone book represents between 8″-10″ in ballistic gelatin. The Golden Saber has again suffered a core-jacket separation resulting in two distinct wound channels. The XTP is holding up like a champ, showing severe tissue damage… and of course the FMJ-FP is just getting warmed up by this point.

Here they are coming out the back of the second phone book…

Apparently, the Golden Saber’s jacket did not exit, and was found lodged in the middle of the second book. Only the bullet core made it through. The XTP on the other hand created a hole so large, that it consumed/engulfed the entire wound channel of the FMJ-FP. Though this particular bullet was not recovered, it shows signs of good structural integrity. The XTP performed how it is supposed to… giving us deep penetration and great expansion. Clearing two phone books is equal to over 16″ in ballistic gelatin.

As for the 200g FMJ-FP, it just plowed right through those two books like a pack of hyenas through a half-eaten zebra carcass. I therefore decided to place four phone books back-to-back, assuming that there was no way it would make it through all of them. Well guess what?… I was wrong. I fired two rounds through four fresh phone books at 7 yards, and both rounds fully penetrated and were not recovered. I would have then tried five books, but by this point I had run out of fresh wet phone books. This means the FMJ-FP load will clear at least 32″-40″ in ballistic gel and still keep on going.

Here are the exit wounds on the back of the fourth book…

The one on the left appears to have tumbled a bit, creating a longer wound channel and knocking the last phone book down as it passed through. These bullets make a great load for the woods where deep penetration is the key to a quick stop with a pistol.

I then decided to fire some JHP’s at the four book’s to see how deep they go, and to recover some expanded bullets. Here are the results…

The XTP held together nicely, retaining an average of 197.33 grains and expanding to an average diameter of 17.61 mm (0.69″)… more than a 70% diameter increase! All rounds were discovered in the beginning of the third book, equating 18″+ of penetration in gelatin. These would make perfect hunting rounds for deer and wild hogs.

Unfortunately, the Golden Saber did not fare so well. Every single recovered bullet had shed its jacket. I have had great results with the Golden Saber bullet design in lower-velocity calibers like 9mm/38+p/40SW/45ACP. However, it consistently failed to hold together in this platform. The average recovered bullet weight was only 126 grains, and the average recovered diameter was 21.27 mm (0.83″) for the jacket and a mere 13.45 mm (0.53″) for the core. The jackets were discovered in the rear half of the second book, and the cores were discovered in the first quarter of the third book. This equates to 14″-18″+ of penetration in calibrated ordinance gelatin.

Despite the core-jacket separations, the Golden Saber load makes a nasty wound channel and doesn’t excessively penetrate. Keep in mind that wet paper is more dense than human body mass, and may be harder on bullets as a result. Therefore, I wouldn’t discredit it as a viable defensive load against 2-legged predators. Just don’t expect it to work miracles through something like an automobile windshield. Perhaps DoubleTap might consider using the newer, bonded Golden Sabers for this load in the future.

Chronograph Velocity Results

5-shot Average @ 10 Feet Glock G20 4.6″ Barrel

1. Golden Saber 165g – 1307 fps / 626 fpe
2. XTP 200g – 1112 fps / 549 fpe
3. FMJ-FP 200g – 1101 fps / 538 fpe

As you can see, these loads did not achieve the firm’s advertised velocities… one would expect about 1140 fps from a 4.6″ barrel. It is not uncommon in the 10mm world for boutique ammo makers to be a little over-blown with their claimed performance… its not just DoubleTap that does it. Despite this, they still performed nicely against the wet mass. And realistically, you can’t expect a lot more in a 4.6″ barrel without going over-pressure. 

Is it just an over-priced .40 S&W?

Some folks claim that the 10mm Auto is just an overpriced version of its offspring, the .40 S&W. I guess if you look at modern factory ammo from the big names, they may be right in making this claim. After all, much of the 10mm big box factory ammo is loaded down to virtual .40 levels; with 200g loads running at around ~1000 fps. Needless to say, this is not “real” 10mm Auto folks. It is watered-down, liability-resistant, .40 S&W loaded into a 10mm Auto case, and stamped with a bloated price tag. The “real” loads, the ones that are closer to original Norma specs, are elevated to a much higher performance class.

This is a similar test using a Glock model 23, and firing a .40 S&W 155g bonded Winchester Ranger JHP… a round considered by many to be one of the better factory loads on the market. The exit wound was 3″ end-to-end…

Nothing against the .40… its a great all-around defensive cartridge, and a well-balanced compromise between power and shoot-ability. But as you can see, it is not quite the same beast.

The diagnosis: 10mm Auto kicks some serious butt when using full-power loads. Plus, a simple barrel swap allows you to fire cheaper .40 S&W out of your Glock. So I ask the nay-sayers, whats not to like?

Be safe out there, and happy shooting.

Adiga Armory